Buying reman longblock stock 5.7 mercruiser OR Vortec 5.7??

SDB

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1992 Rinker Captiva 206 with Mercruiser 5.7 motor. Block cracked from lack of winterization...starts and runs just blows water everywhere and oul looks like milkshake. Thinking buying reman longblock will be best bet. Can do stock 5.7 replacement or can get 5 7 with Vortec heads for same price. Aside from needing new intake manifold for Vortec heads...what else would I need to buy that I can't reuse from old engine?
pulleys/accessories?
fuel pump?
different carb or rejet?
Etc...

any help would be appreciated
 

Rick Stephens

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I'd do the upgrade in a flat second. Yes, needs different manifold. Probably needs rejetting.

And other issues are that most Vortec blocks will have serpentine belt setup as opposed to a V-belt setup. And you nailed it - no Vortec block will have a mechanical fuel pump port. Have to go electric.
 

SDB

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So electric fuel pump, intake manifold, pulley/belt setup is all I would need to change as well as rejetting the carb? Any ideas on places to get a pulley/belt setup and untake manifold?
 

Rick Stephens

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So electric fuel pump, intake manifold, pulley/belt setup is all I would need to change as well as rejetting the carb? Any ideas on places to get a pulley/belt setup and untake manifold?

Personally I'd get a pre-vortec short block and buy the Vortec heads and intake separately. Basically that's what the 4.3L is in my boat. That way I didn't have to change all the bolt on accessories up front to get serp belted stuff.
 

Bondo

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1992 Rinker Captiva 206 with Mercruiser 5.7 motor. Block cracked from lack of winterization...starts and runs just blows water everywhere and oul looks like milkshake. Thinking buying reman longblock will be best bet. Can do stock 5.7 replacement or can get 5 7 with Vortec heads for same price. Aside from needing new intake manifold for Vortec heads...what else would I need to buy that I can't reuse from old engine?
pulleys/accessories?
fuel pump?
different carb or rejet?
Etc...

any help would be appreciated

Ayuh,..... Welcome Aboard,...... Go for the Vortec long block,.....

Yer pulleys, belts, 'n accessories will mount up to it,....
Bein' a '92, ya might already have an electric fuel pump, which the Vortec block will need,....
If it's got a mechanical, ya, ya need an electric one,.... 'n proper wirin',....

Ya haven't said which carb ya got now, if a 2bbl, spring for an edlebrock 1409 4bbl, 'n matchin' intake manifold,.....
If a Quadra-jet, or Merc/ Weber AFB, no need to change anything,....
 

Rick Stephens

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Ayuh,..... Welcome Aboard,...... Go for the Vortec long block,.....

Yer pulleys, belts, 'n accessories will mount up to it,....
Bein' a '92, ya might already have an electric fuel pump, which the Vortec block will need,....
If it's got a mechanical, ya, ya need an electric one,.... 'n proper wirin',....

Ya haven't said which carb ya got now, if a 2bbl, spring for an edlebrock 1409 4bbl, 'n matchin' intake manifold,.....
If a Quadra-jet, or Merc/ Weber AFB, no need to change anything,....

Really? I thought all the pulleys and attached accessories changed to serpentine starting sometime in 96 forward. I guess that means the front seal and balancer is the same either way? Learning something here.
 

Bondo

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Thinking buying reman longblock will be best bet.

Ayuh,...... He's buyin' a long block crate motor, I believe,.....

No pulleys on a long block, gotta use the dressin's from the take-out motor,.....
 

NHGuy

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Get yourself an air gap manifold. Dual plane aluminum. Unless you are in salt water then get either a lined water jacket aluminum or get an iron dual plane.
 

SDB

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Thanks for all the suggestions...maybe I can order my reman motor to be old style block like I have just with Vortec heads/valvetrain....then get an intake....have to look at my carb and see what it is.. if I only have to buy and intake and rejet my carb I will get the vortec heads...I know they are good for at least 30 hp
 

SDB

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This is the boat and trailer just bought Sunday morning...m guy had it listed for a bunch..then changed it to $1000. I was lucky enough to looking at FB Marketplace exactly when he redid ad...contacted him and drove directly to his house about 45 min away with my truck and got ir. He owned it 20+ years never had an issue ...put brand new starter and battery in it and when he went to stary it water everywhere....had it in pole barn but didn't winterize it soon enough....inthink he was pissed/disgusted and wanted to get rid of it right then and there. Came with life javlckets, stereo, air horn, manuals, skis, oars, anchor/ropes/buoys....4 blade prob and 3 blade prop...and $2.84 in change in cup holder! I wanted a Pontoon but felt like for $1000 a boat/trailer combo was a good deal and it's clean/good shape....interior nice...everything seems to work just needs a new longblock. I cam do the mechanical work myself with a mechanic friend at his shop and have and other friend that works at a Marina. I cam get a Jasper motor for 2850 (since my core is bad) or a Michigan Motorz longblock for $2500 with tax if I pickup (2 hrs away). So I'll be in the whole project.for $3k cash and some labor....can't get hurt that way. Bought a nice cover and going to clean/detail/polish/wax it this weekend weather permitting.
 

Scott Danforth

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I would buy a 377 or 383 stroker myself
 

SDB

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I don't want to change the Alpha drive unit and I was told not to go much over 300 hp. Trying to be cheap as possible on this project....but year a 383 would be great! I am going to try to call Michigan Motorz and verify that I can reuse my belts/pulleys from my original block on the Vortec block and if so I'll order that one.
 

Scott Danforth

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plenty of 6.2 strokers in front of alpha drives...... just have to watch your hole shot,...... and you need to run a rev limiter if you ever come out of the water, the re-entry will kill the drive.

However even a 5.7 can grenade an alpha if you come out of the water.

you may need 1/4" spacers behind a few pulleys and brackets to fit your old accessories.
 

SDB

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I'm going to order the reman Vortec long block....get a cast iron Vortec intake....check the carb...see if it has electric fuel pump.....get new water pump....and check/replace all the other bits and pieces...just want tonget it in the water enough this year to break in motor and then store for winter.

thanks for the input
 

tank1949

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So electric fuel pump, intake manifold, pulley/belt setup is all I would need to change as well as rejetting the carb? Any ideas on places to get a pulley/belt setup and untake manifold?

Electric pumps can be a pain to install since you have to add an oil safety switch. Do not use cheap automotive electric pumps. Use MC or Sierra.
 

Scott Danforth

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Sierra is a re-branded Carter. skip the rebranding and get a Carter P4389 universal marine fuel pump
 

NHGuy

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Take a lot of pictures of the old engine setup. They are so valuable.

I recommend doing a run out the boat to check your setup.

I made a run stand out of 2 x 10's. Measure the width and length. Put some 2x4 blocks at the front mount locations.to give the front mounts a spot to land on. Make the rear cross piece a little shorter so the engine can sit level. Voila.

Get yourself a manual oil pressure gauge ($20) and install it to the oil pressure port. Get a fixture from the hardware store so you can send town water to the cooling system. You needa side fuel tank, maybe from your lawnmower, and stick the fuel supply line in there.
An infrared temperature gauge, but you can feel the temperature at the t stat by hand in a pinch. Too hot to touch is too hot to run. Carb engines run at 150 or 160 degrees.

To power your ignition, run a ground wire to the block and hot to the starter. Make a little u bend of thick wire and plug in to the appropriate 2 holes in the engine cannon plug, turn on the water, then jump across the starter solenoid to crank the engine.

The things to check are belt alignments, fluid leaks and engine running condition should be perfect cuz new. If the engine has a flat tappet cam system it must immediately be run at a minimum of 1800 rpm for it's first 20 or 30 minutes to run in the cam to the .lifters. That's the only time to run an engine fast without warming it first.
 
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